An exhaust system includes pipe sections that are welded together. Typically, one end of a pipe is inserted into an open end of a connecting pipe and the pipes are brazed or welded together via a peripheral joint that extends about an inner or outer circumference of the pipes at the connection interface.
As known, the pipes are not sized to fit perfectly together. As such, a clearance exists between the two pipes prior to welding. The circumferential weld provided about the periphery to connect the pipes together fills in this clearance to provide a leak free connection. However, this circumferential weld creates a stress riser that extends 360 degrees around the pipes at the connection interface. This joint is subjected to high heat and high levels of vibration which can cause cracks to be generated at the stress riser. This can result in premature wear and/or fracture of the joint.
Brazing also has some disadvantages. This connection method requires additional brazing material, requires high grade pipe material, and has temperature limits.